Segment Reporting and Geographic Information (Tables)

12 Months Ended

Dec. 31, 2013

Segment Reporting and Geographic Information [Abstract]

Revenue from External Customers by Products and Services [Table Text Block]

The following table lists the different sources of revenue:

	Year Ended December 31,
	2011				2012				2013
Systems and software:
Inspection	$	91,825	49	%	$	128,917	59	%	$	89,089	51	%
Metrology	38,616		21	%	38,001		17	%	26,500		15	%
Data analysis and review	23,356		13	%	19,840		9	%	17,927		10	%
Lithography	—		—	%	—		—	%	8,548		5	%
Parts	21,719		11	%	20,802		10	%	21,078		12	%
Services	11,680		6	%	10,926		5	%	13,096		7	%
Total revenue	$	187,196	100	%	$	218,486	100	%	$	176,238	100	%

Schedule of Revenue from External Customers Attributed to Foreign Countries by Geographic Area [Table Text Block]

The Company’s significant operations outside the United States include sales, service and application offices in Europe and Asia. For geographical reporting, revenues are attributed to the geographic location in which the product is shipped. Revenue by geographic region is as follows:

	Year Ended December 31,
	2011		2012		2013
Revenues from third parties:
United States	$	52,910	$	42,108	$	40,849
Taiwan	26,898		62,239		54,682
South Korea	26,725		33,675		10,704
Singapore	16,344		26,183		17,260
Austria	15,960		11,423		898
Japan	14,925		16,405		7,326
Germany	14,657		5,393		5,669
China	11,124		12,266		20,061
Other Europe	7,653		8,794		18,789
Total revenue	$	187,196	$	218,486	$	176,238

Schedule of Revenue by Major Customers by Reporting Segments [Table Text Block]

The following customers each accounted for more than 10% of total revenues for the indicated periods:

Year Ended December 31,
2011	2012	2013
Infineon Technologies	Samsung Semiconductor Inc.	Intel Semiconductor Inc.
Samsung Semiconductor Inc.	Advanced Semiconductor Engineering, Inc.	STATS ChipPAC Ltd.